>Checked the hive with 18 Queen cells. All are hatched. Didn't find a one of em! Any suggestions?
There is probably only one left now and she will be hard to find for another couple of weeks.
>Does a newly hatched queen look like a full grown queen?
Much smaller. Much faster. Much shyer. I've OFTEN found virgin queens on the sides or bottom of the hive or even outside on the landing board. They are not easy to find.
>I wanted to install divider boards, but was late getting to the cells and now can't find these ladies. Will they just all mate in the next few days and duke it out?
They have probably already duked it out.
>I'd timed them so I think they may have all hatched yesterday. Any input?
One or two probably emerged, the rest probably were killed in their cells. the one or two probably fought it out already.
>How many days till the virgin queen mates? One book I have says 3-4.
It will be several days before she even takes an orientation flight. Antother several days of mating and several more days before she starts to lay. I always figure two weeks before I expect to see eggs. If you don't see them in three weeks, she's never going to be a laying queen.
>What does she do in the meantime?
Runs all over the hive like a maniac trying to make sure she's killed her rivals and leaving her scent everywhere.
>Will we see the mating flight if we pay attention?
If you watch them 24 hours a day for the next two weeks.

The orientation and mating flights usually get a following for a little ways. Kind of like a little swarm.
> (I have two hives in my back yard so we are watching them all the time. Good learning opportunity!)
Have fun.